/****************************************************************
 *
 * The author of this software is David M. Gay.
 *
 * Copyright (c) 1991, 2000, 2001 by Lucent Technologies.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose without fee is hereby granted, provided that this entire notice
 * is included in all copies of any software which is or includes a copy
 * or modification of this software and in all copies of the supporting
 * documentation for such software.
 *
 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHOR NOR LUCENT MAKES ANY
 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
 * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
 *
 ***************************************************************/

/* Please send bug reports to David M. Gay (dmg at acm dot org,
 * with " at " changed at "@" and " dot " changed to ".").	*/

/* On a machine with IEEE extended-precision registers, it is
 * necessary to specify double-precision (53-bit) rounding precision
 * before invoking strtod or dtoa.  If the machine uses (the equivalent
 * of) Intel 80x87 arithmetic, the call
 *	_control87(PC_53, MCW_PC);
 * does this with many compilers.  Whether this or another call is
 * appropriate depends on the compiler; for this to work, it may be
 * necessary to #include "float.h" or another system-dependent header
 * file.
 */

/* strtod for IEEE-, VAX-, and IBM-arithmetic machines.
 *
 * This strtod returns a nearest machine number to the input decimal
 * string (or sets errno to ERANGE).  With IEEE arithmetic, ties are
 * broken by the IEEE round-even rule.  Otherwise ties are broken by
 * biased rounding (add half and chop).
 *
 * Inspired loosely by William D. Clinger's paper "How to Read Floating
 * Point Numbers Accurately" [Proc. ACM SIGPLAN '90, pp. 92-101].
 *
 * Modifications:
 *
 *	1. We only require IEEE, IBM, or VAX double-precision
 *		arithmetic (not IEEE double-extended).
 *	2. We get by with floating-point arithmetic in a case that
 *		Clinger missed -- when we're computing d * 10^n
 *		for a small integer d and the integer n is not too
 *		much larger than 22 (the maximum integer k for which
 *		we can represent 10^k exactly), we may be able to
 *		compute (d*10^k) * 10^(e-k) with just one roundoff.
 *	3. Rather than a bit-at-a-time adjustment of the binary
 *		result in the hard case, we use floating-point
 *		arithmetic to determine the adjustment to within
 *		one bit; only in really hard cases do we need to
 *		compute a second residual.
 *	4. Because of 3., we don't need a large table of powers of 10
 *		for ten-to-e (just some small tables, e.g. of 10^k
 *		for 0 <= k <= 22).
 */

/*
 * This file has been modified to remove dtoa() and all
 * non-reentrancy.  This makes it slower, but it also makes life a lot
 * easier on Windows and other platforms without static lock
 * initializers (grumble).
 */

/* Added by dhuggins@cs.cmu.edu to use autoconf results. */
/* We do not care about the VAX. */
#include "config.h"
#ifdef WORDS_BIGENDIAN
#define IEEE_MC68k
#else
#define IEEE_8087
#endif
#ifndef HAVE_LONG_LONG
#define NO_LONG_LONG
#endif
#define Omit_Private_Memory
#include "sphinxbase/ckd_alloc.h"
#undef USE_LOCALE

/* Correct totally bogus typedefs in this code. */
#include "sphinxbase/prim_type.h"
#define Long int32              /* ZOMG */
#define ULong uint32            /* WTF */

/*
 * #define IEEE_8087 for IEEE-arithmetic machines where the least
 *	significant byte has the lowest address.
 * #define IEEE_MC68k for IEEE-arithmetic machines where the most
 *	significant byte has the lowest address.
 * #define Long int on machines with 32-bit ints and 64-bit longs.
 * #define IBM for IBM mainframe-style floating-point arithmetic.
 * #define VAX for VAX-style floating-point arithmetic (D_floating).
 * #define No_leftright to omit left-right logic in fast floating-point
 *	computation of dtoa.
 * #define Honor_FLT_ROUNDS if FLT_ROUNDS can assume the values 2 or 3
 *	and strtod and dtoa should round accordingly.
 * #define Check_FLT_ROUNDS if FLT_ROUNDS can assume the values 2 or 3
 *	and Honor_FLT_ROUNDS is not #defined.
 * #define RND_PRODQUOT to use rnd_prod and rnd_quot (assembly routines
 *	that use extended-precision instructions to compute rounded
 *	products and quotients) with IBM.
 * #define ROUND_BIASED for IEEE-format with biased rounding.
 * #define Inaccurate_Divide for IEEE-format with correctly rounded
 *	products but inaccurate quotients, e.g., for Intel i860.
 * #define NO_LONG_LONG on machines that do not have a "long long"
 *	integer type (of >= 64 bits).  On such machines, you can
 *	#define Just_16 to store 16 bits per 32-bit Long when doing
 *	high-precision integer arithmetic.  Whether this speeds things
 *	up or slows things down depends on the machine and the number
 *	being converted.  If long long is available and the name is
 *	something other than "long long", #define Llong to be the name,
 *	and if "unsigned Llong" does not work as an unsigned version of
 *	Llong, #define #ULLong to be the corresponding unsigned type.
 * #define Bad_float_h if your system lacks a float.h or if it does not
 *	define some or all of DBL_DIG, DBL_MAX_10_EXP, DBL_MAX_EXP,
 *	FLT_RADIX, FLT_ROUNDS, and DBL_MAX.
 * #define MALLOC your_malloc, where your_malloc(n) acts like malloc(n)
 *	if memory is available and otherwise does something you deem
 *	appropriate.  If MALLOC is undefined, malloc will be invoked
 *	directly -- and assumed always to succeed.
 * #define Omit_Private_Memory to omit logic (added Jan. 1998) for making
 *	memory allocations from a private pool of memory when possible.
 *	When used, the private pool is PRIVATE_MEM bytes long:  2304 bytes,
 *	unless #defined to be a different length.  This default length
 *	suffices to get rid of MALLOC calls except for unusual cases,
 *	such as decimal-to-binary conversion of a very long string of
 *	digits.  The longest string dtoa can return is about 751 bytes
 *	long.  For conversions by strtod of strings of 800 digits and
 *	all dtoa conversions in single-threaded executions with 8-byte
 *	pointers, PRIVATE_MEM >= 7400 appears to suffice; with 4-byte
 *	pointers, PRIVATE_MEM >= 7112 appears adequate.
 * #define NO_INFNAN_CHECK if you do not wish to have INFNAN_CHECK
 *	#defined automatically on IEEE systems.  On such systems,
 *	when INFNAN_CHECK is #defined, strtod checks
 *	for Infinity and NaN (case insensitively).  On some systems
 *	(e.g., some HP systems), it may be necessary to #define NAN_WORD0
 *	appropriately -- to the most significant word of a quiet NaN.
 *	(On HP Series 700/800 machines, -DNAN_WORD0=0x7ff40000 works.)
 *	When INFNAN_CHECK is #defined and No_Hex_NaN is not #defined,
 *	strtod also accepts (case insensitively) strings of the form
 *	NaN(x), where x is a string of hexadecimal digits and spaces;
 *	if there is only one string of hexadecimal digits, it is taken
 *	for the 52 fraction bits of the resulting NaN; if there are two
 *	or more strings of hex digits, the first is for the high 20 bits,
 *	the second and subsequent for the low 32 bits, with intervening
 *	white space ignored; but if this results in none of the 52
 *	fraction bits being on (an IEEE Infinity symbol), then NAN_WORD0
 *	and NAN_WORD1 are used instead.
 * #define MULTIPLE_THREADS if the system offers preemptively scheduled
 *	multiple threads.  In this case, you must provide (or suitably
 *	#define) two locks, acquired by ACQUIRE_DTOA_LOCK(n) and freed
 *	by FREE_DTOA_LOCK(n) for n = 0 or 1.  (The second lock, accessed
 *	in pow5mult, ensures lazy evaluation of only one copy of high
 *	powers of 5; omitting this lock would introduce a small
 *	probability of wasting memory, but would otherwise be harmless.)
 *	You must also invoke freedtoa(s) to free the value s returned by
 *	dtoa.  You may do so whether or not MULTIPLE_THREADS is #defined.
 * #define NO_IEEE_Scale to disable new (Feb. 1997) logic in strtod that
 *	avoids underflows on inputs whose result does not underflow.
 *	If you #define NO_IEEE_Scale on a machine that uses IEEE-format
 *	floating-point numbers and flushes underflows to zero rather
 *	than implementing gradual underflow, then you must also #define
 *	Sudden_Underflow.
 * #define YES_ALIAS to permit aliasing certain double values with
 *	arrays of ULongs.  This leads to slightly better code with
 *	some compilers and was always used prior to 19990916, but it
 *	is not strictly legal and can cause trouble with aggressively
 *	optimizing compilers (e.g., gcc 2.95.1 under -O2).
 * #define USE_LOCALE to use the current locale's decimal_point value.
 * #define SET_INEXACT if IEEE arithmetic is being used and extra
 *	computation should be done to set the inexact flag when the
 *	result is inexact and avoid setting inexact when the result
 *	is exact.  In this case, dtoa.c must be compiled in
 *	an environment, perhaps provided by #include "dtoa.c" in a
 *	suitable wrapper, that defines two functions,
 *		int get_inexact(void);
 *		void clear_inexact(void);
 *	such that get_inexact() returns a nonzero value if the
 *	inexact bit is already set, and clear_inexact() sets the
 *	inexact bit to 0.  When SET_INEXACT is #defined, strtod
 *	also does extra computations to set the underflow and overflow
 *	flags when appropriate (i.e., when the result is tiny and
 *	inexact or when it is a numeric value rounded to +-infinity).
 * #define NO_ERRNO if strtod should not assign errno = ERANGE when
 *	the result overflows to +-Infinity or underflows to 0.
 */

#ifndef Long
#define Long long
#endif
#ifndef ULong
typedef unsigned Long ULong;
#endif

#ifdef DEBUG
#include "stdio.h"
#define Bug(x) {fprintf(stderr, "%s\n", x); exit(1);}
#endif

#include "stdlib.h"
#include "string.h"

#ifdef USE_LOCALE
#include "locale.h"
#endif

/* Private memory and other non-reentrant stuff removed. */

#undef IEEE_Arith
#undef Avoid_Underflow
#ifdef IEEE_MC68k
#define IEEE_Arith
#endif
#ifdef IEEE_8087
#define IEEE_Arith
#endif

#ifdef IEEE_Arith
#ifndef NO_INFNAN_CHECK
#undef INFNAN_CHECK
#define INFNAN_CHECK
#endif
#else
#undef INFNAN_CHECK
#endif

#include "errno.h"

#ifdef Bad_float_h

#ifdef IEEE_Arith
#define DBL_DIG 15
#define DBL_MAX_10_EXP 308
#define DBL_MAX_EXP 1024
#define FLT_RADIX 2
#endif                          /*IEEE_Arith */

#ifdef IBM
#define DBL_DIG 16
#define DBL_MAX_10_EXP 75
#define DBL_MAX_EXP 63
#define FLT_RADIX 16
#define DBL_MAX 7.2370055773322621e+75
#endif

#ifdef VAX
#define DBL_DIG 16
#define DBL_MAX_10_EXP 38
#define DBL_MAX_EXP 127
#define FLT_RADIX 2
#define DBL_MAX 1.7014118346046923e+38
#endif

#ifndef LONG_MAX
#define LONG_MAX 2147483647
#endif

#else                           /* ifndef Bad_float_h */
#include "float.h"
#endif                          /* Bad_float_h */

#ifndef __MATH_H__
#include "math.h"
#endif

#if defined(IEEE_8087) + defined(IEEE_MC68k) + defined(VAX) + defined(IBM) != 1
Exactly one of IEEE_8087, IEEE_MC68k, VAX, or IBM should be defined.
#endif
/** Union to extract the bytes of a double */
    typedef union {
    double d;
    ULong L[2];
} U;

#ifdef YES_ALIAS
#define dval(x) x
#ifdef IEEE_8087
#define word0(x) ((ULong *)&x)[1]
#define word1(x) ((ULong *)&x)[0]
#else
#define word0(x) ((ULong *)&x)[0]
#define word1(x) ((ULong *)&x)[1]
#endif
#else
#ifdef IEEE_8087
#define word0(x) ((U*)&x)->L[1]
#define word1(x) ((U*)&x)->L[0]
#else
#define word0(x) ((U*)&x)->L[0]
#define word1(x) ((U*)&x)->L[1]
#endif
#define dval(x) ((U*)&x)->d
#endif

/* The following definition of Storeinc is appropriate for MIPS processors.
 * An alternative that might be better on some machines is
 * #define Storeinc(a,b,c) (*a++ = b << 16 | c & 0xffff)
 */
#if defined(IEEE_8087) + defined(VAX)
#define Storeinc(a,b,c) (((unsigned short *)a)[1] = (unsigned short)b, \
((unsigned short *)a)[0] = (unsigned short)c, a++)
#else
#define Storeinc(a,b,c) (((unsigned short *)a)[0] = (unsigned short)b, \
((unsigned short *)a)[1] = (unsigned short)c, a++)
#endif

/* #define P DBL_MANT_DIG */
/* Ten_pmax = floor(P*log(2)/log(5)) */
/* Bletch = (highest power of 2 < DBL_MAX_10_EXP) / 16 */
/* Quick_max = floor((P-1)*log(FLT_RADIX)/log(10) - 1) */
/* Int_max = floor(P*log(FLT_RADIX)/log(10) - 1) */

#ifdef IEEE_Arith
#define Exp_shift  20
#define Exp_shift1 20
#define Exp_msk1    0x100000
#define Exp_msk11   0x100000
#define Exp_mask  0x7ff00000
#define P 53
#define Bias 1023
#define Emin (-1022)
#define Exp_1  0x3ff00000
#define Exp_11 0x3ff00000
#define Ebits 11
#define Frac_mask  0xfffff
#define Frac_mask1 0xfffff
#define Ten_pmax 22
#define Bletch 0x10
#define Bndry_mask  0xfffff
#define Bndry_mask1 0xfffff
#define LSB 1
#define Sign_bit 0x80000000
#define Log2P 1
#define Tiny0 0
#define Tiny1 1
#define Quick_max 14
#define Int_max 14
#ifndef NO_IEEE_Scale
#define Avoid_Underflow
#ifdef Flush_Denorm             /* debugging option */
#undef Sudden_Underflow
#endif
#endif

#ifndef Flt_Rounds
#ifdef FLT_ROUNDS
#define Flt_Rounds FLT_ROUNDS
#else
#define Flt_Rounds 1
#endif
#endif                          /*Flt_Rounds */

#ifdef Honor_FLT_ROUNDS
#define Rounding rounding
#undef Check_FLT_ROUNDS
#define Check_FLT_ROUNDS
#else
#define Rounding Flt_Rounds
#endif

#else                           /* ifndef IEEE_Arith */
#undef Check_FLT_ROUNDS
#undef Honor_FLT_ROUNDS
#undef SET_INEXACT
#undef  Sudden_Underflow
#define Sudden_Underflow
#ifdef IBM
#undef Flt_Rounds
#define Flt_Rounds 0
#define Exp_shift  24
#define Exp_shift1 24
#define Exp_msk1   0x1000000
#define Exp_msk11  0x1000000
#define Exp_mask  0x7f000000
#define P 14
#define Bias 65
#define Exp_1  0x41000000
#define Exp_11 0x41000000
#define Ebits 8                 /* exponent has 7 bits, but 8 is the right value in b2d */
#define Frac_mask  0xffffff
#define Frac_mask1 0xffffff
#define Bletch 4
#define Ten_pmax 22
#define Bndry_mask  0xefffff
#define Bndry_mask1 0xffffff
#define LSB 1
#define Sign_bit 0x80000000
#define Log2P 4
#define Tiny0 0x100000
#define Tiny1 0
#define Quick_max 14
#define Int_max 15
#else                           /* VAX */
#undef Flt_Rounds
#define Flt_Rounds 1
#define Exp_shift  23
#define Exp_shift1 7
#define Exp_msk1    0x80
#define Exp_msk11   0x800000
#define Exp_mask  0x7f80
#define P 56
#define Bias 129
#define Exp_1  0x40800000
#define Exp_11 0x4080
#define Ebits 8
#define Frac_mask  0x7fffff
#define Frac_mask1 0xffff007f
#define Ten_pmax 24
#define Bletch 2
#define Bndry_mask  0xffff007f
#define Bndry_mask1 0xffff007f
#define LSB 0x10000
#define Sign_bit 0x8000
#define Log2P 1
#define Tiny0 0x80
#define Tiny1 0
#define Quick_max 15
#define Int_max 15
#endif                          /* IBM, VAX */
#endif                          /* IEEE_Arith */

#ifndef IEEE_Arith
#define ROUND_BIASED
#endif

#ifdef RND_PRODQUOT
#define rounded_product(a,b) a = rnd_prod(a, b)
#define rounded_quotient(a,b) a = rnd_quot(a, b)
extern double rnd_prod(double, double), rnd_quot(double, double);
#else
#define rounded_product(a,b) a *= b
#define rounded_quotient(a,b) a /= b
#endif

#define Big0 (Frac_mask1 | Exp_msk1*(DBL_MAX_EXP+Bias-1))
#define Big1 0xffffffff

#ifndef Pack_32
#define Pack_32
#endif

#define FFFFFFFF 0xffffffffUL

#ifdef NO_LONG_LONG
#undef ULLong
#ifdef Just_16
#undef Pack_32
/* When Pack_32 is not defined, we store 16 bits per 32-bit Long.
 * This makes some inner loops simpler and sometimes saves work
 * during multiplications, but it often seems to make things slightly
 * slower.  Hence the default is now to store 32 bits per Long.
 */
#endif
#else                           /* long long available */
#ifndef Llong
#define Llong long long
#endif
#ifndef ULLong
#define ULLong unsigned Llong
#endif
#endif                          /* NO_LONG_LONG */

#ifndef MULTIPLE_THREADS
#define ACQUIRE_DTOA_LOCK(n)    /*nothing */
#define FREE_DTOA_LOCK(n)       /*nothing */
#endif

#define Kmax 15

#ifdef __cplusplus
extern "C" double sb_strtod(const char *s00, char **se);
#endif

struct Bigint {
    struct Bigint *next;
    int k, maxwds, sign, wds;
    ULong x[1];
};

typedef struct Bigint Bigint;

static Bigint *
Balloc(int k)
{
    int x;
    size_t len;
    Bigint *rv;

    x = 1 << k;
    len = (sizeof(Bigint) + (x - 1) * sizeof(ULong) + sizeof(double) - 1)
        / sizeof(double);
    rv = ckd_malloc(len * sizeof(double));
    rv->k = k;
    rv->maxwds = x;
    rv->sign = rv->wds = 0;
    return rv;
}

static void
Bfree(Bigint * v)
{
    ckd_free(v);
}

#define Bcopy(x,y) memcpy((char *)&x->sign, (char *)&y->sign, \
y->wds*sizeof(Long) + 2*sizeof(int))

static Bigint *
multadd(Bigint * b, int m, int a)
{                               /* multiply by m and add a */
    int i, wds;
#ifdef ULLong
    ULong *x;
    ULLong carry, y;
#else
    ULong carry, *x, y;
#ifdef Pack_32
    ULong xi, z;
#endif
#endif
    Bigint *b1;

    wds = b->wds;
    x = b->x;
    i = 0;
    carry = a;
    do {
#ifdef ULLong
        y = *x * (ULLong) m + carry;
        carry = y >> 32;
        *x++ = y & FFFFFFFF;
#else
#ifdef Pack_32
        xi = *x;
        y = (xi & 0xffff) * m + carry;
        z = (xi >> 16) * m + (y >> 16);
        carry = z >> 16;
        *x++ = (z << 16) + (y & 0xffff);
#else
        y = *x * m + carry;
        carry = y >> 16;
        *x++ = y & 0xffff;
#endif
#endif
    } while (++i < wds);
    if (carry) {
        if (wds >= b->maxwds) {
            b1 = Balloc(b->k + 1);
            Bcopy(b1, b);
            Bfree(b);
            b = b1;
        }
        b->x[wds++] = (uint32) carry;
        b->wds = wds;
    }
    return b;
}

static Bigint *
s2b(const char *s, int nd0, int nd, ULong y9)
{
    Bigint *b;
    int i, k;
    Long x, y;

    x = (nd + 8) / 9;
    for (k = 0, y = 1; x > y; y <<= 1, k++);
#ifdef Pack_32
    b = Balloc(k);
    b->x[0] = y9;
    b->wds = 1;
#else
    b = Balloc(k + 1);
    b->x[0] = y9 & 0xffff;
    b->wds = (b->x[1] = y9 >> 16) ? 2 : 1;
#endif

    i = 9;
    if (9 < nd0) {
        s += 9;
        do
            b = multadd(b, 10, *s++ - '0');
        while (++i < nd0);
        s++;
    }
    else
        s += 10;
    for (; i < nd; i++)
        b = multadd(b, 10, *s++ - '0');
    return b;
}

static int
hi0bits(register ULong x)
{
    register int k = 0;

    if (!(x & 0xffff0000)) {
        k = 16;
        x <<= 16;
    }
    if (!(x & 0xff000000)) {
        k += 8;
        x <<= 8;
    }
    if (!(x & 0xf0000000)) {
        k += 4;
        x <<= 4;
    }
    if (!(x & 0xc0000000)) {
        k += 2;
        x <<= 2;
    }
    if (!(x & 0x80000000)) {
        k++;
        if (!(x & 0x40000000))
            return 32;
    }
    return k;
}

static int
lo0bits(ULong * y)
{
    register int k;
    register ULong x = *y;

    if (x & 7) {
        if (x & 1)
            return 0;
        if (x & 2) {
            *y = x >> 1;
            return 1;
        }
        *y = x >> 2;
        return 2;
    }
    k = 0;
    if (!(x & 0xffff)) {
        k = 16;
        x >>= 16;
    }
    if (!(x & 0xff)) {
        k += 8;
        x >>= 8;
    }
    if (!(x & 0xf)) {
        k += 4;
        x >>= 4;
    }
    if (!(x & 0x3)) {
        k += 2;
        x >>= 2;
    }
    if (!(x & 1)) {
        k++;
        x >>= 1;
        if (!x)
            return 32;
    }
    *y = x;
    return k;
}

static Bigint *
i2b(int i)
{
    Bigint *b;

    b = Balloc(1);
    b->x[0] = i;
    b->wds = 1;
    return b;
}

static Bigint *
mult(Bigint * a, Bigint * b)
{
    Bigint *c;
    int k, wa, wb, wc;
    ULong *x, *xa, *xae, *xb, *xbe, *xc, *xc0;
    ULong y;
#ifdef ULLong
    ULLong carry, z;
#else
    ULong carry, z;
#ifdef Pack_32
    ULong z2;
#endif
#endif

    if (a->wds < b->wds) {
        c = a;
        a = b;
        b = c;
    }
    k = a->k;
    wa = a->wds;
    wb = b->wds;
    wc = wa + wb;
    if (wc > a->maxwds)
        k++;
    c = Balloc(k);
    for (x = c->x, xa = x + wc; x < xa; x++)
        *x = 0;
    xa = a->x;
    xae = xa + wa;
    xb = b->x;
    xbe = xb + wb;
    xc0 = c->x;
#ifdef ULLong
    for (; xb < xbe; xc0++) {
        if ((y = *xb++)) {
            x = xa;
            xc = xc0;
            carry = 0;
            do {
                z = *x++ * (ULLong) y + *xc + carry;
                carry = z >> 32;
                *xc++ = z & FFFFFFFF;
            } while (x < xae);
            *xc = (uint32) carry;
        }
    }
#else
#ifdef Pack_32
    for (; xb < xbe; xb++, xc0++) {
        if (y = *xb & 0xffff) {
            x = xa;
            xc = xc0;
            carry = 0;
            do {
                z = (*x & 0xffff) * y + (*xc & 0xffff) + carry;
                carry = z >> 16;
                z2 = (*x++ >> 16) * y + (*xc >> 16) + carry;
                carry = z2 >> 16;
                Storeinc(xc, z2, z);
            }
            while (x < xae);
            *xc = carry;
        }
        if (y = *xb >> 16) {
            x = xa;
            xc = xc0;
            carry = 0;
            z2 = *xc;
            do {
                z = (*x & 0xffff) * y + (*xc >> 16) + carry;
                carry = z >> 16;
                Storeinc(xc, z, z2);
                z2 = (*x++ >> 16) * y + (*xc & 0xffff) + carry;
                carry = z2 >> 16;
            }
            while (x < xae);
            *xc = z2;
        }
    }
#else
    for (; xb < xbe; xc0++) {
        if (y = *xb++) {
            x = xa;
            xc = xc0;
            carry = 0;
            do {
                z = *x++ * y + *xc + carry;
                carry = z >> 16;
                *xc++ = z & 0xffff;
            }
            while (x < xae);
            *xc = carry;
        }
    }
#endif
#endif
    for (xc0 = c->x, xc = xc0 + wc; wc > 0 && !*--xc; --wc);
    c->wds = wc;
    return c;
}

static Bigint *
pow5mult(Bigint * b, int k)
{
    Bigint *b1, *p5, *p51;
    int i;
    static int const p05[3] = { 5, 25, 125 };

    if ((i = k & 3))
        b = multadd(b, p05[i - 1], 0);

    if (!(k >>= 2))
        return b;

    p5 = i2b(625);
    for (;;) {
        if (k & 1) {
            b1 = mult(b, p5);
            Bfree(b);
            b = b1;
        }
        if (!(k >>= 1))
            break;
        p51 = mult(p5, p5);
        Bfree(p5);
        p5 = p51;
    }
    Bfree(p5);
    return b;
}

static Bigint *
lshift(Bigint * b, int k)
{
    int i, k1, n, n1;
    Bigint *b1;
    ULong *x, *x1, *xe, z;

#ifdef Pack_32
    n = k >> 5;
#else
    n = k >> 4;
#endif
    k1 = b->k;
    n1 = n + b->wds + 1;
    for (i = b->maxwds; n1 > i; i <<= 1)
        k1++;
    b1 = Balloc(k1);
    x1 = b1->x;
    for (i = 0; i < n; i++)
        *x1++ = 0;
    x = b->x;
    xe = x + b->wds;
#ifdef Pack_32
    if (k &= 0x1f) {
        k1 = 32 - k;
        z = 0;
        do {
            *x1++ = *x << k | z;
            z = *x++ >> k1;
        } while (x < xe);
        if ((*x1 = z))
            ++n1;
    }
#else
    if (k &= 0xf) {
        k1 = 16 - k;
        z = 0;
        do {
            *x1++ = *x << k & 0xffff | z;
            z = *x++ >> k1;
        }
        while (x < xe);
        if (*x1 = z)
            ++n1;
    }
#endif
    else
        do
            *x1++ = *x++;
        while (x < xe);
    b1->wds = n1 - 1;
    Bfree(b);
    return b1;
}

static int
cmp(Bigint * a, Bigint * b)
{
    ULong *xa, *xa0, *xb, *xb0;
    int i, j;

    i = a->wds;
    j = b->wds;
#ifdef DEBUG
    if (i > 1 && !a->x[i - 1])
        Bug("cmp called with a->x[a->wds-1] == 0");
    if (j > 1 && !b->x[j - 1])
        Bug("cmp called with b->x[b->wds-1] == 0");
#endif
    if (i -= j)
        return i;
    xa0 = a->x;
    xa = xa0 + j;
    xb0 = b->x;
    xb = xb0 + j;
    for (;;) {
        if (*--xa != *--xb)
            return *xa < *xb ? -1 : 1;
        if (xa <= xa0)
            break;
    }
    return 0;
}

static Bigint *
diff(Bigint * a, Bigint * b)
{
    Bigint *c;
    int i, wa, wb;
    ULong *xa, *xae, *xb, *xbe, *xc;
#ifdef ULLong
    ULLong borrow, y;
#else
    ULong borrow, y;
#ifdef Pack_32
    ULong z;
#endif
#endif

    i = cmp(a, b);
    if (!i) {
        c = Balloc(0);
        c->wds = 1;
        c->x[0] = 0;
        return c;
    }
    if (i < 0) {
        c = a;
        a = b;
        b = c;
        i = 1;
    }
    else
        i = 0;
    c = Balloc(a->k);
    c->sign = i;
    wa = a->wds;
    xa = a->x;
    xae = xa + wa;
    wb = b->wds;
    xb = b->x;
    xbe = xb + wb;
    xc = c->x;
    borrow = 0;
#ifdef ULLong
    do {
        y = (ULLong) * xa++ - *xb++ - borrow;
        borrow = y >> 32 & (ULong) 1;
        *xc++ = y & FFFFFFFF;
    } while (xb < xbe);
    while (xa < xae) {
        y = *xa++ - borrow;
        borrow = y >> 32 & (ULong) 1;
        *xc++ = y & FFFFFFFF;
    }
#else
#ifdef Pack_32
    do {
        y = (*xa & 0xffff) - (*xb & 0xffff) - borrow;
        borrow = (y & 0x10000) >> 16;
        z = (*xa++ >> 16) - (*xb++ >> 16) - borrow;
        borrow = (z & 0x10000) >> 16;
        Storeinc(xc, z, y);
    }
    while (xb < xbe);
    while (xa < xae) {
        y = (*xa & 0xffff) - borrow;
        borrow = (y & 0x10000) >> 16;
        z = (*xa++ >> 16) - borrow;
        borrow = (z & 0x10000) >> 16;
        Storeinc(xc, z, y);
    }
#else
    do {
        y = *xa++ - *xb++ - borrow;
        borrow = (y & 0x10000) >> 16;
        *xc++ = y & 0xffff;
    }
    while (xb < xbe);
    while (xa < xae) {
        y = *xa++ - borrow;
        borrow = (y & 0x10000) >> 16;
        *xc++ = y & 0xffff;
    }
#endif
#endif
    while (!*--xc)
        wa--;
    c->wds = wa;
    return c;
}

static double
ulp(double x)
{
    register Long L;
    U a;

    L = (word0(x) & Exp_mask) - (P - 1) * Exp_msk1;
#ifndef Avoid_Underflow
#ifndef Sudden_Underflow
    if (L > 0) {
#endif
#endif
#ifdef IBM
        L |= Exp_msk1 >> 4;
#endif
        word0(a) = L;
        word1(a) = 0;
#ifndef Avoid_Underflow
#ifndef Sudden_Underflow
    }
    else {
        L = -L >> Exp_shift;
        if (L < Exp_shift) {
            word0(a) = 0x80000 >> L;
            word1(a) = 0;
        }
        else {
            word0(a) = 0;
            L -= Exp_shift;
            word1(a) = L >= 31 ? 1 : 1 << 31 - L;
        }
    }
#endif
#endif
    return dval(a);
}

static double
b2d(Bigint * a, int *e)
{
    ULong *xa, *xa0, w, y, z;
    int k;
    U d;
#ifdef VAX
    ULong d0, d1;
#else
#define d0 word0(d)
#define d1 word1(d)
#endif

    xa0 = a->x;
    xa = xa0 + a->wds;
    y = *--xa;
#ifdef DEBUG
    if (!y)
        Bug("zero y in b2d");
#endif
    k = hi0bits(y);
    *e = 32 - k;
#ifdef Pack_32
    if (k < Ebits) {
        d0 = Exp_1 | y >> (Ebits - k);
        w = xa > xa0 ? *--xa : 0;
        d1 = y << ((32 - Ebits) + k) | w >> (Ebits - k);
        goto ret_d;
    }
    z = xa > xa0 ? *--xa : 0;
    if (k -= Ebits) {
        d0 = Exp_1 | y << k | z >> (32 - k);
        y = xa > xa0 ? *--xa : 0;
        d1 = z << k | y >> (32 - k);
    }
    else {
        d0 = Exp_1 | y;
        d1 = z;
    }
#else
    if (k < Ebits + 16) {
        z = xa > xa0 ? *--xa : 0;
        d0 = Exp_1 | y << k - Ebits | z >> Ebits + 16 - k;
        w = xa > xa0 ? *--xa : 0;
        y = xa > xa0 ? *--xa : 0;
        d1 = z << k + 16 - Ebits | w << k - Ebits | y >> 16 + Ebits - k;
        goto ret_d;
    }
    z = xa > xa0 ? *--xa : 0;
    w = xa > xa0 ? *--xa : 0;
    k -= Ebits + 16;
    d0 = Exp_1 | y << k + 16 | z << k | w >> 16 - k;
    y = xa > xa0 ? *--xa : 0;
    d1 = w << k + 16 | y << k;
#endif
  ret_d:
#ifdef VAX
    word0(d) = d0 >> 16 | d0 << 16;
    word1(d) = d1 >> 16 | d1 << 16;
#else
#undef d0
#undef d1
#endif
    return dval(d);
}

static Bigint *
d2b(double _d, int *e, int *bits)
{
    Bigint *b;
    int de, k;
    ULong *x, y, z;
    U d;
#ifndef Sudden_Underflow
    int i;
#endif
#ifdef VAX
    ULong d0, d1;
    d0 = word0(d) >> 16 | word0(d) << 16;
    d1 = word1(d) >> 16 | word1(d) << 16;
#else
#define d0 word0(d)
#define d1 word1(d)
#endif
    dval(d) = _d;

#ifdef Pack_32
    b = Balloc(1);
#else
    b = Balloc(2);
#endif
    x = b->x;

    z = d0 & Frac_mask;
    d0 &= 0x7fffffff;           /* clear sign bit, which we ignore */
#ifdef Sudden_Underflow
    de = (int) (d0 >> Exp_shift);
#ifndef IBM
    z |= Exp_msk11;
#endif
#else
    if ((de = (int) (d0 >> Exp_shift)))
        z |= Exp_msk1;
#endif
#ifdef Pack_32
    if ((y = d1)) {
        if ((k = lo0bits(&y))) {
            x[0] = y | z << (32 - k);
            z >>= k;
        }
        else
            x[0] = y;
#ifndef Sudden_Underflow
        i =
#endif
            b->wds = (x[1] = z) ? 2 : 1;
    }
    else {
#ifdef DEBUG
        if (!z)
            Bug("Zero passed to d2b");
#endif
        k = lo0bits(&z);
        x[0] = z;
#ifndef Sudden_Underflow
        i =
#endif
            b->wds = 1;
        k += 32;
    }
#else
    if (y = d1) {
        if (k = lo0bits(&y))
            if (k >= 16) {
                x[0] = y | z << 32 - k & 0xffff;
                x[1] = z >> k - 16 & 0xffff;
                x[2] = z >> k;
                i = 2;
            }
            else {
                x[0] = y & 0xffff;
                x[1] = y >> 16 | z << 16 - k & 0xffff;
                x[2] = z >> k & 0xffff;
                x[3] = z >> k + 16;
                i = 3;
            }
        else {
            x[0] = y & 0xffff;
            x[1] = y >> 16;
            x[2] = z & 0xffff;
            x[3] = z >> 16;
            i = 3;
        }
    }
    else {
#ifdef DEBUG
        if (!z)
            Bug("Zero passed to d2b");
#endif
        k = lo0bits(&z);
        if (k >= 16) {
            x[0] = z;
            i = 0;
        }
        else {
            x[0] = z & 0xffff;
            x[1] = z >> 16;
            i = 1;
        }
        k += 32;
    }
    while (!x[i])
        --i;
    b->wds = i + 1;
#endif
#ifndef Sudden_Underflow
    if (de) {
#endif
#ifdef IBM
        *e = (de - Bias - (P - 1) << 2) + k;
        *bits = 4 * P + 8 - k - hi0bits(word0(d) & Frac_mask);
#else
        *e = de - Bias - (P - 1) + k;
        *bits = P - k;
#endif
#ifndef Sudden_Underflow
    }
    else {
        *e = de - Bias - (P - 1) + 1 + k;
#ifdef Pack_32
        *bits = 32 * i - hi0bits(x[i - 1]);
#else
        *bits = (i + 2) * 16 - hi0bits(x[i]);
#endif
    }
#endif
    return b;
}

#undef d0
#undef d1

static double
ratio(Bigint * a, Bigint * b)
{
    U da, db;
    int k, ka, kb;

    dval(da) = b2d(a, &ka);
    dval(db) = b2d(b, &kb);
#ifdef Pack_32
    k = ka - kb + 32 * (a->wds - b->wds);
#else
    k = ka - kb + 16 * (a->wds - b->wds);
#endif
#ifdef IBM
    if (k > 0) {
        word0(da) += (k >> 2) * Exp_msk1;
        if (k &= 3)
            dval(da) *= 1 << k;
    }
    else {
        k = -k;
        word0(db) += (k >> 2) * Exp_msk1;
        if (k &= 3)
            dval(db) *= 1 << k;
    }
#else
    if (k > 0)
        word0(da) += k * Exp_msk1;
    else {
        k = -k;
        word0(db) += k * Exp_msk1;
    }
#endif
    return dval(da) / dval(db);
}

static const double tens[] =
    { 1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
    1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20,
    1e21,
    1e22
#ifdef VAX
        , 1e23, 1e24
#endif
};

static const double
#ifdef IEEE_Arith
 bigtens[] = { 1e16, 1e32, 1e64, 1e128, 1e256 };

static const double tinytens[] = { 1e-16, 1e-32, 1e-64, 1e-128,
#ifdef Avoid_Underflow
    9007199254740992. * 9007199254740992.e-256
/* = 2^106 * 1e-53 */
#else
    1e-256
#endif
};

/* The factor of 2^53 in tinytens[4] helps us avoid setting the underflow */
/* flag unnecessarily.  It leads to a song and dance at the end of strtod. */
#define Scale_Bit 0x10
#define n_bigtens 5
#else
#ifdef IBM
bigtens[] = { 1e16, 1e32, 1e64 };
static const double tinytens[] = { 1e-16, 1e-32, 1e-64 };

#define n_bigtens 3
#else
bigtens[] = { 1e16, 1e32 };
static const double tinytens[] = { 1e-16, 1e-32 };

#define n_bigtens 2
#endif
#endif

#ifdef INFNAN_CHECK

#ifndef NAN_WORD0
#define NAN_WORD0 0x7ff80000
#endif

#ifndef NAN_WORD1
#define NAN_WORD1 0
#endif

static int
match(const char **sp, char *t)
{
    int c, d;
    const char *s = *sp;

    while ((d = *t++)) {
        if ((c = *++s) >= 'A' && c <= 'Z')
            c += 'a' - 'A';
        if (c != d)
            return 0;
    }
    *sp = s + 1;
    return 1;
}

#ifndef No_Hex_NaN
static void
hexnan(U * rvp, const char **sp)
{
    ULong c, x[2];
    const char *s;
    int havedig, udx0, xshift;

    x[0] = x[1] = 0;
    havedig = xshift = 0;
    udx0 = 1;
    s = *sp;
    /* allow optional initial 0x or 0X */
    while ((c = *(const unsigned char *) (s + 1)) && c <= ' ')
        ++s;
    if (s[1] == '0' && (s[2] == 'x' || s[2] == 'X'))
        s += 2;
    while ((c = *(const unsigned char *) ++s)) {
        if (c >= '0' && c <= '9')
            c -= '0';
        else if (c >= 'a' && c <= 'f')
            c += 10 - 'a';
        else if (c >= 'A' && c <= 'F')
            c += 10 - 'A';
        else if (c <= ' ') {
            if (udx0 && havedig) {
                udx0 = 0;
                xshift = 1;
            }
            continue;
        }
#ifdef GDTOA_NON_PEDANTIC_NANCHECK
        else if ( /*( */ c == ')' && havedig) {
            *sp = s + 1;
            break;
        }
        else
            return;             /* invalid form: don't change *sp */
#else
        else {
            do {
                if ( /*( */ c == ')') {
                    *sp = s + 1;
                    break;
                }
            } while ((c = *++s));
            break;
        }
#endif
        havedig = 1;
        if (xshift) {
            xshift = 0;
            x[0] = x[1];
            x[1] = 0;
        }
        if (udx0)
            x[0] = (x[0] << 4) | (x[1] >> 28);
        x[1] = (x[1] << 4) | c;
    }
    if ((x[0] &= 0xfffff) || x[1]) {
        word0(*rvp) = Exp_mask | x[0];
        word1(*rvp) = x[1];
    }
}
#endif                          /*No_Hex_NaN */
#endif                          /* INFNAN_CHECK */

double
sb_strtod(const char *s00, char **se)
{
#ifdef Avoid_Underflow
    int scale;
#endif
    int bb2, bb5, bbe, bd2, bd5, bbbits, bs2, c, dsign, e, e1, esign,
        i, j, k, nd, nd0, nf, nz, nz0, sign;
    const char *s, *s0, *s1;
    double aadj, adj;
    U rv, rv0, aadj1;
    Long L;
    ULong y, z;
    Bigint *bb = NULL, *bb1, *bd = NULL, *bd0, *bs = NULL, *delta = NULL;
#ifdef SET_INEXACT
    int inexact, oldinexact;
#endif
#ifdef Honor_FLT_ROUNDS
    int rounding;
#endif
#ifdef USE_LOCALE
    const char *s2;
#endif

    sign = nz0 = nz = 0;
    dval(rv) = 0.;
    for (s = s00;; s++)
        switch (*s) {
        case '-':
            sign = 1;
            /* no break */
        case '+':
            if (*++s)
                goto break2;
            /* no break */
        case 0:
            goto ret0;
        case '\t':
        case '\n':
        case '\v':
        case '\f':
        case '\r':
        case ' ':
            continue;
        default:
            goto break2;
        }
  break2:if (*s == '0') {
        nz0 = 1;
        while (*++s == '0');
        if (!*s)
            goto ret;
    }
    s0 = s;
    y = z = 0;
    for (nd = nf = 0; (c = *s) >= '0' && c <= '9'; nd++, s++)
        if (nd < 9)
            y = 10 * y + c - '0';
        else if (nd < 16)
            z = 10 * z + c - '0';
    nd0 = nd;
#ifdef USE_LOCALE
    s1 = localeconv()->decimal_point;
    if (c == *s1) {
        c = '.';
        if (*++s1) {
            s2 = s;
            for (;;) {
                if (*++s2 != *s1) {
                    c = 0;
                    break;
                }
                if (!*++s1) {
                    s = s2;
                    break;
                }
            }
        }
    }
#endif
    if (c == '.') {
        c = *++s;
        if (!nd) {
            for (; c == '0'; c = *++s)
                nz++;
            if (c > '0' && c <= '9') {
                s0 = s;
                nf += nz;
                nz = 0;
                goto have_dig;
            }
            goto dig_done;
        }
        for (; c >= '0' && c <= '9'; c = *++s) {
          have_dig:nz++;
            if (c -= '0') {
                nf += nz;
                for (i = 1; i < nz; i++)
                    if (nd++ < 9)
                        y *= 10;
                    else if (nd <= DBL_DIG + 1)
                        z *= 10;
                if (nd++ < 9)
                    y = 10 * y + c;
                else if (nd <= DBL_DIG + 1)
                    z = 10 * z + c;
                nz = 0;
            }
        }
    }
  dig_done:e = 0;
    if (c == 'e' || c == 'E') {
        if (!nd && !nz && !nz0) {
            goto ret0;
        }
        s00 = s;
        esign = 0;
        switch (c = *++s) {
        case '-':
            esign = 1;
        case '+':
            c = *++s;
        }
        if (c >= '0' && c <= '9') {
            while (c == '0')
                c = *++s;
            if (c > '0' && c <= '9') {
                L = c - '0';
                s1 = s;
                while ((c = *++s) >= '0' && c <= '9')
                    L = 10 * L + c - '0';
                if (s - s1 > 8 || L > 19999)
                    /* Avoid confusion from exponents
                     * so large that e might overflow.
                     */
                    e = 19999;  /* safe for 16 bit ints */
                else
                    e = (int) L;
                if (esign)
                    e = -e;
            }
            else
                e = 0;
        }
        else
            s = s00;
    }
    if (!nd) {
        if (!nz && !nz0) {
#ifdef INFNAN_CHECK
            /* Check for Nan and Infinity */
            switch (c) {
            case 'i':
            case 'I':
                if (match(&s, "nf")) {
                    --s;
                    if (!match(&s, "inity"))
                        ++s;
                    word0(rv) = 0x7ff00000;
                    word1(rv) = 0;
                    goto ret;
                }
                break;
            case 'n':
            case 'N':
                if (match(&s, "an")) {
                    word0(rv) = NAN_WORD0;
                    word1(rv) = NAN_WORD1;
#ifndef No_Hex_NaN
                    if (*s == '(')      /*) */
                        hexnan(&rv, &s);
#endif
                    goto ret;
                }
            }
#endif                          /* INFNAN_CHECK */
          ret0:
            s = s00;
            sign = 0;
        }
        goto ret;
    }
    e1 = e -= nf;

    /* Now we have nd0 digits, starting at s0, followed by a
     * decimal point, followed by nd-nd0 digits.  The number we're
     * after is the integer represented by those digits times
     * 10**e */

    if (!nd0)
        nd0 = nd;
    k = nd < DBL_DIG + 1 ? nd : DBL_DIG + 1;
    dval(rv) = y;
    if (k > 9) {
#ifdef SET_INEXACT
        if (k > DBL_DIG)
            oldinexact = get_inexact();
#endif
        dval(rv) = tens[k - 9] * dval(rv) + z;
    }
    bd0 = 0;
    if (nd <= DBL_DIG
#ifndef RND_PRODQUOT
#ifndef Honor_FLT_ROUNDS
        && Flt_Rounds == 1
#endif
#endif
        ) {
        if (!e)
            goto ret;
        if (e > 0) {
            if (e <= Ten_pmax) {
#ifdef VAX
                goto vax_ovfl_check;
#else
#ifdef Honor_FLT_ROUNDS
                /* round correctly FLT_ROUNDS = 2 or 3 */
                if (sign) {
                    rv = -rv;
                    sign = 0;
                }
#endif
                /* rv = */ rounded_product(dval(rv), tens[e]);
                goto ret;
#endif
            }
            i = DBL_DIG - nd;
            if (e <= Ten_pmax + i) {
                /* A fancier test would sometimes let us do
                 * this for larger i values.
                 */
#ifdef Honor_FLT_ROUNDS
                /* round correctly FLT_ROUNDS = 2 or 3 */
                if (sign) {
                    rv = -rv;
                    sign = 0;
                }
#endif
                e -= i;
                dval(rv) *= tens[i];
#ifdef VAX
                /* VAX exponent range is so narrow we must
                 * worry about overflow here...
                 */
              vax_ovfl_check:
                word0(rv) -= P * Exp_msk1;
                /* rv = */ rounded_product(dval(rv), tens[e]);
                if ((word0(rv) & Exp_mask)
                    > Exp_msk1 * (DBL_MAX_EXP + Bias - 1 - P))
                    goto ovfl;
                word0(rv) += P * Exp_msk1;
#else
                /* rv = */ rounded_product(dval(rv), tens[e]);
#endif
                goto ret;
            }
        }
#ifndef Inaccurate_Divide
        else if (e >= -Ten_pmax) {
#ifdef Honor_FLT_ROUNDS
            /* round correctly FLT_ROUNDS = 2 or 3 */
            if (sign) {
                rv = -rv;
                sign = 0;
            }
#endif
            /* rv = */ rounded_quotient(dval(rv), tens[-e]);
            goto ret;
        }
#endif
    }
    e1 += nd - k;

#ifdef IEEE_Arith
#ifdef SET_INEXACT
    inexact = 1;
    if (k <= DBL_DIG)
        oldinexact = get_inexact();
#endif
#ifdef Avoid_Underflow
    scale = 0;
#endif
#ifdef Honor_FLT_ROUNDS
    if ((rounding = Flt_Rounds) >= 2) {
        if (sign)
            rounding = rounding == 2 ? 0 : 2;
        else if (rounding != 2)
            rounding = 0;
    }
#endif
#endif                          /*IEEE_Arith */

    /* Get starting approximation = rv * 10**e1 */

    if (e1 > 0) {
        if ((i = e1 & 15))
            dval(rv) *= tens[i];
        if (e1 &= ~15) {
            if (e1 > DBL_MAX_10_EXP) {
              ovfl:
#ifndef NO_ERRNO
                errno = ERANGE;
#endif
                /* Can't trust HUGE_VAL */
#ifdef IEEE_Arith
#ifdef Honor_FLT_ROUNDS
                switch (rounding) {
                case 0:        /* toward 0 */
                case 3:        /* toward -infinity */
                    word0(rv) = Big0;
                    word1(rv) = Big1;
                    break;
                default:
                    word0(rv) = Exp_mask;
                    word1(rv) = 0;
                }
#else                           /*Honor_FLT_ROUNDS */
                word0(rv) = Exp_mask;
                word1(rv) = 0;
#endif                          /*Honor_FLT_ROUNDS */
#ifdef SET_INEXACT
                /* set overflow bit */
                dval(rv0) = 1e300;
                dval(rv0) *= dval(rv0);
#endif
#else                           /*IEEE_Arith */
                word0(rv) = Big0;
                word1(rv) = Big1;
#endif                          /*IEEE_Arith */
                if (bd0)
                    goto retfree;
                goto ret;
            }
            e1 >>= 4;
            for (j = 0; e1 > 1; j++, e1 >>= 1)
                if (e1 & 1)
                    dval(rv) *= bigtens[j];
            /* The last multiplication could overflow. */ word0(rv) -=
                P * Exp_msk1;
            dval(rv) *= bigtens[j];
            if ((z = word0(rv) & Exp_mask)
                > Exp_msk1 * (DBL_MAX_EXP + Bias - P))
                goto ovfl;
            if (z > Exp_msk1 * (DBL_MAX_EXP + Bias - 1 - P)) {
                /* set to largest number */
                /* (Can't trust DBL_MAX) */
                word0(rv) = Big0;
                word1(rv) = Big1;
            }
            else
                word0(rv) += P * Exp_msk1;
        }
    }
    else if (e1 < 0) {
        e1 = -e1;
        if ((i = e1 & 15))
            dval(rv) /= tens[i];
        if (e1 >>= 4) {
            if (e1 >= 1 << n_bigtens)
                goto undfl;

#ifdef Avoid_Underflow
            if (e1 & Scale_Bit)
                scale = 2 * P;
            for (j = 0; e1 > 0; j++, e1 >>= 1)
                if (e1 & 1)
                    dval(rv) *= tinytens[j];
            if (scale && (j = 2 * P + 1 - ((word0(rv) & Exp_mask)
                                           >> Exp_shift)) > 0) {
                /* scaled rv is denormal; zap j low bits */
                if (j >= 32) {
                    word1(rv) = 0;
                    if (j >= 53)
                        word0(rv) = (P + 2) * Exp_msk1;
                    else
                        word0(rv) &= 0xffffffff << (j - 32);
                }
                else
                    word1(rv) &= 0xffffffff << j;
            }

            if (!dval(rv)) {
              undfl:
                dval(rv) = 0.;
#ifndef NO_ERRNO
                errno = ERANGE;
#endif
                if (bd0)
                    goto retfree;
                goto ret;
            }
#else
            for (j = 0; e1 > 1; j++, e1 >>= 1)
                if (e1 & 1)
                    dval(rv) *= tinytens[j];
            /* The last multiplication could underflow. */
            dval(rv0) = dval(rv);
            dval(rv) *= tinytens[j];
            if (!dval(rv)) {
                dval(rv) = 2. * dval(rv0);
                dval(rv) *= tinytens[j];

                if (!dval(rv)) {
                  undfl:
                    dval(rv) = 0.;
#ifndef NO_ERRNO
                    errno = ERANGE;
#endif
                    if (bd0)
                        goto retfree;
                    goto ret;
                }
                word0(rv) = Tiny0;
                word1(rv) = Tiny1;
                /* The refinement below will clean
                 * this approximation up.
                 */
            }
#endif
        }
    }

    /* Now the hard part -- adjusting rv to the correct value. */

    /* Put digits into bd: true value = bd * 10^e */

    bd0 = s2b(s0, nd0, nd, y);

    for (;;) {
        bd = Balloc(bd0->k);
        Bcopy(bd, bd0);
        bb = d2b(dval(rv), &bbe, &bbbits);      /* rv = bb * 2^bbe */
        bs = i2b(1);

        if (e >= 0) {
            bb2 = bb5 = 0;
            bd2 = bd5 = e;
        }
        else {
            bb2 = bb5 = -e;
            bd2 = bd5 = 0;
        }
        if (bbe >= 0)
            bb2 += bbe;
        else
            bd2 -= bbe;
        bs2 = bb2;
#ifdef Honor_FLT_ROUNDS
        if (rounding != 1)
            bs2++;
#endif
#ifdef Avoid_Underflow
        j = bbe - scale;
        i = j + bbbits - 1;     /* logb(rv) */
        if (i < Emin)           /* denormal */
            j += P - Emin;
        else
            j = P + 1 - bbbits;
#else                           /*Avoid_Underflow */
#ifdef Sudden_Underflow
#ifdef IBM
        j = 1 + 4 * P - 3 - bbbits + ((bbe + bbbits - 1) & 3);
#else
        j = P + 1 - bbbits;
#endif
#else                           /*Sudden_Underflow */
        j = bbe;
        i = j + bbbits - 1;     /* logb(rv) */
        if (i < Emin)           /* denormal */
            j += P - Emin;
        else
            j = P + 1 - bbbits;
#endif                          /*Sudden_Underflow */
#endif                          /*Avoid_Underflow */
        bb2 += j;
        bd2 += j;
#ifdef Avoid_Underflow
        bd2 += scale;
#endif
        i = bb2 < bd2 ? bb2 : bd2;
        if (i > bs2)
            i = bs2;
        if (i > 0) {
            bb2 -= i;
            bd2 -= i;
            bs2 -= i;
        }
        if (bb5 > 0) {
            bs = pow5mult(bs, bb5);
            bb1 = mult(bs, bb);
            Bfree(bb);
            bb = bb1;
        }
        if (bb2 > 0)
            bb = lshift(bb, bb2);
        if (bd5 > 0)
            bd = pow5mult(bd, bd5);
        if (bd2 > 0)
            bd = lshift(bd, bd2);
        if (bs2 > 0)
            bs = lshift(bs, bs2);
        delta = diff(bb, bd);
        dsign = delta->sign;
        delta->sign = 0;
        i = cmp(delta, bs);
#ifdef Honor_FLT_ROUNDS
        if (rounding != 1) {
            if (i < 0) {
                /* Error is less than an ulp */
                if (!delta->x[0] && delta->wds <= 1) {
                    /* exact */
#ifdef SET_INEXACT
                    inexact = 0;
#endif
                    break;
                }
                if (rounding) {
                    if (dsign) {
                        adj = 1.;
                        goto apply_adj;
                    }
                }
                else if (!dsign) {
                    adj = -1.;
                    if (!word1(rv)
                        && !(word0(rv) & Frac_mask)) {
                        y = word0(rv) & Exp_mask;
#ifdef Avoid_Underflow
                        if (!scale || y > 2 * P * Exp_msk1)
#else
                        if (y)
#endif
                        {
                            delta = lshift(delta, Log2P);
                            if (cmp(delta, bs) <= 0)
                                adj = -0.5;
                        }
                    }
                  apply_adj:
#ifdef Avoid_Underflow
                    if (scale && (y = word0(rv) & Exp_mask)
                        <= 2 * P * Exp_msk1)
                        word0(adj) += (2 * P + 1) * Exp_msk1 - y;
#else
#ifdef Sudden_Underflow
                    if ((word0(rv) & Exp_mask) <= P * Exp_msk1) {
                        word0(rv) += P * Exp_msk1;
                        dval(rv) += adj * ulp(dval(rv));
                        word0(rv) -= P * Exp_msk1;
                    }
                    else
#endif                          /*Sudden_Underflow */
#endif                          /*Avoid_Underflow */
                        dval(rv) += adj * ulp(dval(rv));
                }
                break;
            }
            adj = ratio(delta, bs);
            if (adj < 1.)
                adj = 1.;
            if (adj <= 0x7ffffffe) {
                /* adj = rounding ? ceil(adj) : floor(adj); */
                y = adj;
                if (y != adj) {
                    if (!((rounding >> 1) ^ dsign))
                        y++;
                    adj = y;
                }
            }
#ifdef Avoid_Underflow
            if (scale && (y = word0(rv) & Exp_mask) <= 2 * P * Exp_msk1)
                word0(adj) += (2 * P + 1) * Exp_msk1 - y;
#else
#ifdef Sudden_Underflow
            if ((word0(rv) & Exp_mask) <= P * Exp_msk1) {
                word0(rv) += P * Exp_msk1;
                adj *= ulp(dval(rv));
                if (dsign)
                    dval(rv) += adj;
                else
                    dval(rv) -= adj;
                word0(rv) -= P * Exp_msk1;
                goto cont;
            }
#endif                          /*Sudden_Underflow */
#endif                          /*Avoid_Underflow */
            adj *= ulp(dval(rv));
            if (dsign)
                dval(rv) += adj;
            else
                dval(rv) -= adj;
            goto cont;
        }
#endif                          /*Honor_FLT_ROUNDS */

        if (i < 0) {
            /* Error is less than half an ulp -- check for
             * special case of mantissa a power of two.
             */
            if (dsign || word1(rv) || word0(rv) & Bndry_mask
#ifdef IEEE_Arith
#ifdef Avoid_Underflow
                || (word0(rv) & Exp_mask) <= (2 * P + 1) * Exp_msk1
#else
                || (word0(rv) & Exp_mask) <= Exp_msk1
#endif
#endif
                ) {
#ifdef SET_INEXACT
                if (!delta->x[0] && delta->wds <= 1)
                    inexact = 0;
#endif
                break;
            }
            if (!delta->x[0] && delta->wds <= 1) {
                /* exact result */
#ifdef SET_INEXACT
                inexact = 0;
#endif
                break;
            }
            delta = lshift(delta, Log2P);
            if (cmp(delta, bs) > 0)
                goto drop_down;
            break;
        }
        if (i == 0) {
            /* exactly half-way between */
            if (dsign) {
                if ((word0(rv) & Bndry_mask1) == Bndry_mask1
                    && word1(rv) == (
#ifdef Avoid_Underflow
                                           (scale
                                            && (y = word0(rv) & Exp_mask)
                                            <= 2 * P * Exp_msk1)
                                           ? (0xffffffff &
                                              (0xffffffff <<
                                               (2 * P + 1 -
                                                (y >> Exp_shift)))) :
#endif
                                           0xffffffff)) {
                    /*boundary case -- increment exponent */
                    word0(rv) = (word0(rv) & Exp_mask)
                        + Exp_msk1
#ifdef IBM
                        | Exp_msk1 >> 4
#endif
                        ;
                    word1(rv) = 0;
#ifdef Avoid_Underflow
                    dsign = 0;
#endif
                    break;
                }
            }
            else if (!(word0(rv) & Bndry_mask) && !word1(rv)) {
              drop_down:
                /* boundary case -- decrement exponent */
#ifdef Sudden_Underflow         /*{{ */
                L = word0(rv) & Exp_mask;
#ifdef IBM
                if (L < Exp_msk1)
#else
#ifdef Avoid_Underflow
                if (L <= (scale ? (2 * P + 1) * Exp_msk1 : Exp_msk1))
#else
                if (L <= Exp_msk1)
#endif                          /*Avoid_Underflow */
#endif               /*IBM*/
                        goto undfl;
                L -= Exp_msk1;
#else                           /*Sudden_Underflow}{ */
#ifdef Avoid_Underflow
                if (scale) {
                    L = word0(rv) & Exp_mask;
                    if (L <= (2 * P + 1) * Exp_msk1) {
                        if (L > (P + 2) * Exp_msk1)
                            /* round even ==> */
                            /* accept rv */
                            break;
                        /* rv = smallest denormal */
                        goto undfl;
                    }
                }
#endif                          /*Avoid_Underflow */
                L = (word0(rv) & Exp_mask) - Exp_msk1;
#endif                          /*Sudden_Underflow}} */
                word0(rv) = L | Bndry_mask1;
                word1(rv) = 0xffffffff;
#ifdef IBM
                goto cont;
#else
                break;
#endif
            }
#ifndef ROUND_BIASED
            if (!(word1(rv) & LSB))
                break;
#endif
            if (dsign)
                dval(rv) += ulp(dval(rv));
#ifndef ROUND_BIASED
            else {
                dval(rv) -= ulp(dval(rv));
#ifndef Sudden_Underflow
                if (!dval(rv))
                    goto undfl;
#endif
            }
#ifdef Avoid_Underflow
            dsign = 1 - dsign;
#endif
#endif
            break;
        }
        if ((aadj = ratio(delta, bs)) <= 2.) {
            if (dsign)
                aadj = dval(aadj1) = 1.;
            else if (word1(rv) || word0(rv) & Bndry_mask) {
#ifndef Sudden_Underflow
                if (word1(rv) == Tiny1 && !word0(rv))
                    goto undfl;
#endif
                aadj = 1.;
                dval(aadj1) = -1.;
            }
            else {
                /* special case -- power of FLT_RADIX to be */
                /* rounded down... */

                if (aadj < 2. / FLT_RADIX)
                    aadj = 1. / FLT_RADIX;
                else
                    aadj *= 0.5;
                dval(aadj1) = -aadj;
            }
        }
        else {
            aadj *= 0.5;
            dval(aadj1) = dsign ? aadj : -aadj;
#ifdef Check_FLT_ROUNDS
            switch (Rounding) {
            case 2:            /* towards +infinity */
                dval(aadj1) -= 0.5;
                break;
            case 0:            /* towards 0 */
            case 3:            /* towards -infinity */
                dval(aadj1) += 0.5;
            }
#else
            if (Flt_Rounds == 0)
                dval(aadj1) += 0.5;
#endif                          /*Check_FLT_ROUNDS */
        }
        y = word0(rv) & Exp_mask;

        /* Check for overflow */

        if (y == Exp_msk1 * (DBL_MAX_EXP + Bias - 1)) {
            dval(rv0) = dval(rv);
            word0(rv) -= P * Exp_msk1;
            adj = dval(aadj1) * ulp(dval(rv));
            dval(rv) += adj;
            if ((word0(rv) & Exp_mask) >=
                Exp_msk1 * (DBL_MAX_EXP + Bias - P)) {
                if (word0(rv0) == Big0 && word1(rv0) == Big1)
                    goto ovfl;
                word0(rv) = Big0;
                word1(rv) = Big1;
                goto cont;
            }
            else
                word0(rv) += P * Exp_msk1;
        }
        else {
#ifdef Avoid_Underflow
            if (scale && y <= 2 * P * Exp_msk1) {
                if (aadj <= 0x7fffffff) {
                    if ((z = (uint32) aadj) <= 0)
                        z = 1;
                    aadj = z;
                    dval(aadj1) = dsign ? aadj : -aadj;
                }
                word0(aadj1) += (2 * P + 1) * Exp_msk1 - y;
            }
            adj = dval(aadj1) * ulp(dval(rv));
            dval(rv) += adj;
#else
#ifdef Sudden_Underflow
            if ((word0(rv) & Exp_mask) <= P * Exp_msk1) {
                dval(rv0) = dval(rv);
                word0(rv) += P * Exp_msk1;
                adj = aadj1 * ulp(dval(rv));
                dval(rv) += adj;
#ifdef IBM
                if ((word0(rv) & Exp_mask) < P * Exp_msk1)
#else
                if ((word0(rv) & Exp_mask) <= P * Exp_msk1)
#endif
                {
                    if (word0(rv0) == Tiny0 && word1(rv0) == Tiny1)
                        goto undfl;
                    word0(rv) = Tiny0;
                    word1(rv) = Tiny1;
                    goto cont;
                }
                else
                    word0(rv) -= P * Exp_msk1;
            }
            else {
                adj = aadj1 * ulp(dval(rv));
                dval(rv) += adj;
            }
#else                           /*Sudden_Underflow */
            /* Compute adj so that the IEEE rounding rules will
             * correctly round rv + adj in some half-way cases.
             * If rv * ulp(rv) is denormalized (i.e.,
             * y <= (P-1)*Exp_msk1), we must adjust aadj to avoid
             * trouble from bits lost to denormalization;
             * example: 1.2e-307 .
             */
            if (y <= (P - 1) * Exp_msk1 && aadj > 1.) {
                aadj1 = (double) (int) (aadj + 0.5);
                if (!dsign)
                    aadj1 = -aadj1;
            }
            adj = aadj1 * ulp(dval(rv));
            dval(rv) += adj;
#endif                          /*Sudden_Underflow */
#endif                          /*Avoid_Underflow */
        }
        z = word0(rv) & Exp_mask;
#ifndef SET_INEXACT
#ifdef Avoid_Underflow
        if (!scale)
#endif
            if (y == z) {
                /* Can we stop now? */
                L = (Long) aadj;
                aadj -= L;
                /* The tolerances below are conservative. */
                if (dsign || word1(rv) || word0(rv) & Bndry_mask) {
                    if (aadj < .4999999 || aadj > .5000001)
                        break;
                }
                else if (aadj < .4999999 / FLT_RADIX)
                    break;
            }
#endif
      cont:Bfree(bb);
        Bfree(bd);
        Bfree(bs);
        Bfree(delta);
    }
#ifdef SET_INEXACT
    if (inexact) {
        if (!oldinexact) {
            word0(rv0) = Exp_1 + (70 << Exp_shift);
            word1(rv0) = 0;
            dval(rv0) += 1.;
        }
    }
    else if (!oldinexact)
        clear_inexact();
#endif
#ifdef Avoid_Underflow
    if (scale) {
        word0(rv0) = Exp_1 - 2 * P * Exp_msk1;
        word1(rv0) = 0;
        dval(rv) *= dval(rv0);
#ifndef NO_ERRNO
        /* try to avoid the bug of testing an 8087 register value */
        if (word0(rv) == 0 && word1(rv) == 0)
            errno = ERANGE;
#endif
    }
#endif                          /* Avoid_Underflow */
#ifdef SET_INEXACT
    if (inexact && !(word0(rv) & Exp_mask)) {
        /* set underflow bit */
        dval(rv0) = 1e-300;
        dval(rv0) *= dval(rv0);
    }
#endif
  retfree:Bfree(bb);
    Bfree(bd);
    Bfree(bs);
    Bfree(bd0);
    Bfree(delta);
  ret:if (se)
        *se = (char *) s;
    return sign ? -dval(rv) : dval(rv);
}
